/*
 * Copyright (c) 2013 Functional Streams for Scala
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package fs2
package hashing

import scala.scalanative.unsafe._
import scala.scalanative.unsigned._

import hashing.openssl._

trait HashingSuitePlatform {
  def digest(algo: HashAlgorithm, str: String): Hash = {
    val name = Hasher.toAlgorithmString(algo)
    val bytes = str.getBytes
    val md = new Array[Byte](EVP_MAX_MD_SIZE)
    val size = stackalloc[CUnsignedInt]()
    val `type` = EVP_get_digestbyname((name + "\u0000").getBytes.atUnsafe(0))
    EVP_Digest(
      if (bytes.length > 0) bytes.atUnsafe(0) else null,
      bytes.length.toUSize,
      md.atUnsafe(0),
      size,
      `type`,
      null
    )
    Hash(Chunk.array(md.take((!size).toInt)))
  }

  def hmac(algo: HashAlgorithm, key: Chunk[Byte], str: String): Hash = {
    val name = Hasher.toAlgorithmString(algo)
    val bytes = str.getBytes
    val md = new Array[Byte](EVP_MAX_MD_SIZE)
    val size = stackalloc[CUnsignedInt]()
    val `type` = EVP_get_digestbyname((name + "\u0000").getBytes.atUnsafe(0))
    val keySlice = key.toArraySlice
    HMAC(
      `type`,
      keySlice.values.atUnsafe(keySlice.offset),
      keySlice.size.toUSize,
      if (bytes.length > 0) bytes.atUnsafe(0) else null,
      bytes.length.toUSize,
      md.atUnsafe(0),
      size
    )
    Hash(Chunk.array(md.take((!size).toInt)))
  }
}
